1. Field of the Invention
This invention generally relates to a bicycle control system that conducts interval communications from a rider operable switch device to a cycle computer. More specifically, the invention relates to a bicycle control system in which a switch operation signal is correctly recognized by a cycle computer even if a communication outage (e.g., interference or interruption in communications) occurs.
2. Background Information
Bicycling is becoming an increasingly more popular form of recreation as well as a means of transportation. Moreover, bicycling has become a very popular competitive sport for both amateurs and professionals. Whether the bicycle is used for recreation, transportation or competition, the bicycle industry is constantly improving the various components of the bicycle.
Recently, bicycles have been equipped with electrical components to make riding easier and more enjoyable for the rider. Some bicycles are equipped with automatic shifting units that are automatically adjusted according to the riding conditions that are determined by a cycle computer or control unit. In particular, the front and rear derailleurs have recently been automated. Moreover, various electronic devices have been used to determine one or more operating parameters for controlling the derailleurs and providing information to the rider. Thus, the cycle computer or control unit of the bicycle not only provides information to the rider, but is also used in controlling various components of the bicycle. Thus, it is desirable to provide reliable and accurate communications between the cycle computer or control unit and the other bicycle components that cooperate together.
In a conventional bicycle control system, the bicycle is provided with a plurality of sensors (speed sensor, cadence sensor, etc.) and a cycle computer. The sensors (speed sensor, cadence sensor, etc.) are connected to the bicycle at various stationary locations such as on a front fork, a chain stay, a seat tube, etc. The cycle computer is typically mounted on the bicycle handlebar. The bicycle cycle computer displays various kinds of information regarding the speed, the pedal revolution per minute (rpm), the gear in operation, the pulse of the rider, the ambient temperature, the geographical height and the like.
Also in a conventional bicycle control system, control switches (gear shift control switch, suspension control switch, display control switch and stop watch control switch et al.) are provided for inputting commands or control signals to the cycle computer. The control switches are attached at grip parts (both ends) of the bicycle handlebar. Typically, wires are used to connect each of the sensors and the control switches to the cycle computer.
More recently, some bicycle control system use wireless communications to communicate signals to the cycle computer. Thus, the cycle computer and the input devices communicate by wireless communications (radio communication, or infrared communication). For example, if an upshift control switch is pressed, the shift control switch sends a switch signal to the cycle computer. When the cycle computer receives the switch signal, the cycle computer determines what this signal is, what does this signal means, and what the value of the signal is. After, the cycle computer detects and interprets “this signal is an upshift signal”, and sends a command signal that directs a (front or rear) derailleur to upshift. In this conventional system, the cycle computer needs time for detecting and interpreting the signal from the switch unit. Thus, the data can not be transmitted and received in real time. Therefore, if a communication outage happens due some interference or interruption in communications, then the data may be unrecognizable or falsely recognized.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved bicycle control system. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.